1. Field of the Invention
The present invention relates to a hitpoint sensor which precisely measures the location of an energetic impact on a surface of interest. More specifically, it relates to a hitpoint sensor which precisely measures the location of energetic impact on a surface of interest, and which provides the measurement rapidly and efficiently.
2. Description of the Related Art
In many military and commercial applications it is usually necessary to measure the precise location of energetic impacts on a surface of interest.
One of the primary areas of application is in the field of missile defense where it is desired to destroy incoming enemy missiles. One approach to achieving this goal is with kinetic energy systems, which destroy enemy missiles by impacting them with kinetic energy from one or more projectiles. In the development and testing of these systems, it is necessary to be able to determine the precise location of the kinetic energy impact on the surface of the simulated enemy missile.
Other examples include the determination of the impact location of kinetic energy rounds targeting enemy ground assets for the purposes of weapon system development and testing or real-time battle damage assessment.
Existing hitpoint sensor systems either detect or estimate the location of kinetic energy collisions on surfaces. Conventional systems are generally of two types: electrical and optical. Electrical systems include the Coaxial Hit Grid (CHG) developed by Battelle Corporation. The CHG uses a grid of coaxial cable to estimate the impact location of a kinetic energy collision.
An example of an optical system is the Photonic Hit Indicator (PHI) developed by ITT. The PHI is a fiber-optic grid that is designed to provide unique impact location indications for different flight test targets. Another example of an optical system is the Blast Initiation Detector (BID) developed by Johns Hopkins University Applied Physics Laboratory (JHU APL). The BID detects the time of a collision by viewing the exterior of the surface. The BID is a high-speed instrument that detects rapid-onset optical events. It has a wide field-of-view and uses high-temperature optical fibers that maintain their field-of-view and optical throughput during the rapid heating that occurs during reentry into the earth's atmosphere. Another example of an optical system is the Planar Optical Penetration Sensors, also developed by JHU APL.
While these hitpoint sensor systems accomplish their intended purpose of detecting or locating energetic impacts on a surface of interest, they suffer from a number of drawbacks. Existing electrical systems often suffer from electromagnetic interference (EMI) that can corrupt the information and cause erroneous conclusions. Existing optical and electrical systems typically have high channel counts requiring high-speed sampling systems and associated complex data processing systems.
Related aspects of these designs include the needs for external power sources and data compression techniques. These requirements can present a number of drawbacks: First, external power sources can be awkward and unnecessarily burdensome, often limiting the utility of a system which is intended to be operated as an adjunct test device to a primary system undergoing test and evaluation procedures. Secondly, data compression techniques further complicate the design, and can present additional issues to the system. One issue may be time transmission of information associated with the impact location. In the case of a target system, there may be very little time to transmit the information before the system itself is destroyed; therefore, efficient encoding of the information associated with the impact location is very desirable.
In order to overcome these problems, what is needed is a simple to use hitpoint sensor, which does not require distributed electrical power and which uses low channel count and which is relatively immune to EMI, thus addressing and solving problems associated with conventional systems.